The present invention relates to an apparatus for use in turning steerable vehicle wheels.
A known apparatus for use in turning steerable vehicle wheels includes a housing which is connected with a frame of a vehicle. The housing encloses a piston. A hollow piston rod extends from the piston and projects outward from one end of the housing. The piston rod is connected with a vehicle steering linkage. A compensator chamber is provided in the hollow piston rod to enable the working areas on opposite sides of the piston to be equalized. A power steering apparatus having this construction is disclosed in U.S. Pat. Nos. 4,418,781 and 4,475,440.
The aforementioned power steering apparatus includes a piston and cylinder type motor having one end connected to a frame of a vehicle and the opposite end connected with a steering linkage. However, it has been suggested that a central portion of a piston and cylinder type power steering motor could be connected with a vehicle steering linkage. In this apparatus, a pair of pistons cooperate with opposite ends of a housing to form chambers. A connector section disposed between the pistons is connected with a vehicle steering linkage. A steering apparatus having this construction is disclosed in U.S. Pat. Nos. 4,646,868 and 4,815,552.